<span>The four biological macromolecules are carbohydrates, lipids, proteins and nucleic acid. These macromolecules are known as polymers and are built when monomers join together by a process known as the dehydration reaction. The dehydration reaction is a chemical reaction that produces water (H2O) and the result is the covalent bonding of the two monomer molecules. The monomer molecules consist of nutrients found in the soil, as in the case of plants, and the intake of food as in the case of animals.
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The correct answer is "C".
Onion cell is a plant cell and human cheek cell is an animal cell. Hence, onion cell has a cell wall<span> but not in human cheek cells because animal cells do not have cell wall. Both cells have single nucleus. Since, human cheek cell is an animal cell, chloroplasts are cannot be seen in the human cheek cells.</span>
there is no clear evidence about plants evolving in the desert, or fossils of any kind of cactus despite their distribution over a large area. But, scientists are of the opinion that they acquired specific attributes millions of years ago, as a response to the vastly changing climate and conditions.
-Desert plant root system
A typical desert plant has a deep root system, which is a specific physical mechanism. As the roots grow deep down the soil, they absorb soil water, which is then transported to the upper portions of the plant.
-Desert plant leaves
Bear small foliage with waxy surface to minimize transpiration (loss of water through stomatal pores), which in turn, helps to conserve water.
Explanation:
who many chambers does the heart has
